merge from gcc

1 files changed, 166 insertions, 0 deletions

diff --git a/libiberty/pex-unix.c b/libiberty/pex-unix.c
new file mode 100644
index 0000000..14fe71e
--- /dev/null
+++ b/libiberty/pex-unix.c
@@ -0,0 +1,166 @@
+/* Utilities to execute a program in a subprocess (possibly linked by pipes
+   with other subprocesses), and wait for it.  Generic Unix version
+   (also used for UWIN and VMS).
+   Copyright (C) 1996, 1997, 1998, 1999, 2000, 2001, 2003
+   Free Software Foundation, Inc.
+
+This file is part of the libiberty library.
+Libiberty is free software; you can redistribute it and/or
+modify it under the terms of the GNU Library General Public
+License as published by the Free Software Foundation; either
+version 2 of the License, or (at your option) any later version.
+
+Libiberty is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Library General Public License for more details.
+
+You should have received a copy of the GNU Library General Public
+License along with libiberty; see the file COPYING.LIB.  If not,
+write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+Boston, MA 02111-1307, USA.  */
+
+#include "pex-common.h"
+
+#include <stdio.h>
+#include <errno.h>
+#ifdef NEED_DECLARATION_ERRNO
+extern int errno;
+#endif
+#ifdef HAVE_STRING_H
+#include <string.h>
+#endif
+#ifdef HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+#ifdef HAVE_STDLIB_H
+#include <stdlib.h>
+#endif
+#ifdef HAVE_SYS_WAIT_H
+#include <sys/wait.h>
+#endif
+
+#ifndef HAVE_WAITPID
+#define waitpid(pid, status, flags) wait(status)
+#endif
+
+extern int execv ();
+extern int execvp ();
+
+int
+pexecute (program, argv, this_pname, temp_base, errmsg_fmt, errmsg_arg, flags)
+     const char *program;
+     char * const *argv;
+     const char *this_pname;
+     const char *temp_base ATTRIBUTE_UNUSED;
+     char **errmsg_fmt, **errmsg_arg;
+     int flags;
+{
+  int (*func)() = (flags & PEXECUTE_SEARCH ? execvp : execv);
+  int pid;
+  int pdes[2];
+  int input_desc, output_desc;
+  int retries, sleep_interval;
+  /* Pipe waiting from last process, to be used as input for the next one.
+     Value is STDIN_FILE_NO if no pipe is waiting
+     (i.e. the next command is the first of a group).  */
+  static int last_pipe_input;
+
+  /* If this is the first process, initialize.  */
+  if (flags & PEXECUTE_FIRST)
+    last_pipe_input = STDIN_FILE_NO;
+
+  input_desc = last_pipe_input;
+
+  /* If this isn't the last process, make a pipe for its output,
+     and record it as waiting to be the input to the next process.  */
+  if (! (flags & PEXECUTE_LAST))
+    {
+      if (pipe (pdes) < 0)
+	{
+	  *errmsg_fmt = "pipe";
+	  *errmsg_arg = NULL;
+	  return -1;
+	}
+      output_desc = pdes[WRITE_PORT];
+      last_pipe_input = pdes[READ_PORT];
+    }
+  else
+    {
+      /* Last process.  */
+      output_desc = STDOUT_FILE_NO;
+      last_pipe_input = STDIN_FILE_NO;
+    }
+
+  /* Fork a subprocess; wait and retry if it fails.  */
+  sleep_interval = 1;
+  pid = -1;
+  for (retries = 0; retries < 4; retries++)
+    {
+      pid = fork ();
+      if (pid >= 0)
+	break;
+      sleep (sleep_interval);
+      sleep_interval *= 2;
+    }
+
+  switch (pid)
+    {
+    case -1:
+      *errmsg_fmt = "fork";
+      *errmsg_arg = NULL;
+      return -1;
+
+    case 0: /* child */
+      /* Move the input and output pipes into place, if necessary.  */
+      if (input_desc != STDIN_FILE_NO)
+	{
+	  close (STDIN_FILE_NO);
+	  dup (input_desc);
+	  close (input_desc);
+	}
+      if (output_desc != STDOUT_FILE_NO)
+	{
+	  close (STDOUT_FILE_NO);
+	  dup (output_desc);
+	  close (output_desc);
+	}
+
+      /* Close the parent's descs that aren't wanted here.  */
+      if (last_pipe_input != STDIN_FILE_NO)
+	close (last_pipe_input);
+
+      /* Exec the program.  */
+      (*func) (program, argv);
+
+      fprintf (stderr, "%s: ", this_pname);
+      fprintf (stderr, install_error_msg, program);
+      fprintf (stderr, ": %s\n", xstrerror (errno));
+      exit (-1);
+      /* NOTREACHED */
+      return 0;
+
+    default:
+      /* In the parent, after forking.
+	 Close the descriptors that we made for this child.  */
+      if (input_desc != STDIN_FILE_NO)
+	close (input_desc);
+      if (output_desc != STDOUT_FILE_NO)
+	close (output_desc);
+
+      /* Return child's process number.  */
+      return pid;
+    }
+}
+
+int
+pwait (pid, status, flags)
+     int pid;
+     int *status;
+     int flags ATTRIBUTE_UNUSED;
+{
+  /* ??? Here's an opportunity to canonicalize the values in STATUS.
+     Needed?  */
+  pid = waitpid (pid, status, 0);
+  return pid;
+}